Ho Phu, a fisherman in Phu Dien Commune of Thua Thien – Hue Province, discovered the marine turtle, which is named in the red list of threatened species, when he was fishing on Monday.

He informed local authorities and later released it to the sea.

The species is protected from being caught and exploited for any purpose by Vietnamese laws.

Nguyen Quang Vinh Binh, chief of the province’s Marine Resources Protection and Exploitation Agency, said his agency has rescued five other sea turtles discovered in the laggon since March 7.

Another one was dead when local fishermen attempted to keep it in a shrimp farm.

Binh called the phenomenon “very strange” and “rare,” since locals used to see a sea turtle in the lagoon just once in every few years.

The agency had reported the phenomenon to higher agencies, he said.

It takes a sea turtle 30-40 years to grow up and reach its productive stage, Binh said.

Male turtles rarely return to shore, while females come ashore during their nesting season, usually between February and June on the lunar calendar. Even then they often choose sandy beaches without noises and light to lay eggs, he said.